In the sport of golf, the golfer strikes a golf ball with a golf club. The golf club includes an elongated club shaft, which is attached at one end to an enlarged club head and is wrapped at the other end with a gripping material to form a handle. The clubs are divided into several groups, depending upon the function of the club. These groups include the drivers, the irons (including wedges for the present purposes), and the putters.
Because golf has become a highly popular spectator and participant sport, a great deal of development effort has been devoted to golf clubs. Both the design of the clubs and the materials of construction have been improved in recent years. The present invention deals primarily with the materials of construction of golf clubs, and the following discussion will emphasize that subject area.
Until recent years, both the club shaft and the club head have been made primarily of metals such as steel and/or aluminum alloys. Composite-material shafts made of graphite-fiber-reinforced polymeric materials have been introduced, to reduce the weight and increase the material stiffness of the shaft. Heads made of specialty materials such as titanium alloys have been developed, to achieve reduced club head mass and density with high material stiffness so that the club head speed may be increased. The use of such materials also permits the manufacture of a larger-sized club head with the same mass or with redistributed weight and better performance. This brief discussion of new materials used in golf club shafts and heads is by no means exhaustive, and many other materials have been tried in order to achieve particular club behavior based upon various theories of club performance.
There remains a need, however, for further improvements in golf clubs in order to attain high durability and toughness of hitting face at low stiffness levels and high strength at low weight. These properties, in turn, lead to higher club head speed and a higher degree of energy transfer from the club to the ball upon impact, thereby permitting any player to perform to the best of his or her ability without being limited by the nature of the golf clubs. The present invention fulfills this need, and further provides related advantages.